Washington: Pakistan-born Canadian Tahawwur Rana`s terrorism trial revealed the impunity with which officers in Pakistan`s Inter-Services Intelligence (ISI) and terrorists alike operate in Pakistan, according to ProPublica, an investigative news group.

The case also showed how a growing number of serving and former Pakistani military officers have put their lethal talents at the service of Lashkar-e-Toiba terror group behind the 2008 Mumbai attacks, al Qaeda and other groups, it said analysing the implications of the trial that ended on Thursday.

Confessed American terrorist and Pakistani spy David Coleman Headley, ProPublica noted delivered explosive revelations about how ISI officers funded, supported and directed the 26/11 Mumbai attacks along with the LeT.

The trial also left enduring mysteries, ProPublica said noting it did not answer questions about whether Sajid Mir, a Lashkar mastermind caught on tape directing the slaughter in Mumbai by phone, was once a Pakistani military officer.

It did not explore the extent to which ISI chiefs beyond Headley`s handler, known only as Major Iqbal, were aware of the Mumbai plot.

Headley testified that he believed top ISI leadership was not aware, but he also said he thought Iqbal`s commanding officer and his unit of the spy agency knew about the operation, the investigative group noted.

Describing Rana`s conviction on two of three counts as a "small victory", ProPublica noted Washington has been pressing Pakistan for more than a year to arrest Major Iqbal as well as Mir and a half-a-dozen other Lashkar chiefs who have been implicated as masterminds.

Despite abundant evidence and the US federal indictment, the Pakistani government has not pursued those fugitives. They are not in hiding and continue to be involved in terrorist plotting, it said citing US investigators.

Lashkar is simply too powerful and too close to the Pakistani security forces, according to Western and Indian counter-terror officials cited by ProPublica.